virtio: initialize earlier

Move initialization of the virtio framework before the initialization of
mtd, so that block2mtd can be used on virtio-based block devices.

Addresses https://bugzilla.kernel.org/show_bug.cgi?id=15644

Signed-off-by: Stijn Tintel <stijn@linux-ipv6.be>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: stable@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/Makefile

@@ -17,6 +17,7 @@ obj-$(CONFIG_SFI)		+= sfi/
 obj-$(CONFIG_PNP)		+= pnp/
 obj-$(CONFIG_ARM_AMBA)		+= amba/
 
+obj-$(CONFIG_VIRTIO)		+= virtio/
 obj-$(CONFIG_XEN)		+= xen/
 
 # regulators early, since some subsystems rely on them to initialize
@@ -108,7 +109,6 @@ obj-$(CONFIG_PPC_PS3)		+= ps3/
 obj-$(CONFIG_OF)		+= of/
 obj-$(CONFIG_SSB)		+= ssb/
 obj-$(CONFIG_VHOST_NET)		+= vhost/
-obj-$(CONFIG_VIRTIO)		+= virtio/
 obj-$(CONFIG_VLYNQ)		+= vlynq/
 obj-$(CONFIG_STAGING)		+= staging/
 obj-y				+= platform/